text不可设置默认值 null empty string 前者update 初始值时 我响应,但不报错
SQL Server 2008 Constants 類別 Constants 欄位 C# 閱讀英文 儲存 新增至集合 新增至計劃 共用方式為 Facebookx.comLinkedIn電子郵件 列印 發行項 2010/09/24 本文內容 語法 請參閱 The default empty size. 命名空間:Microsoft.ReportingServices.RdlObjectModel ...
default(TSource) if source is empty or if no element passes the test specified by predicate; otherwise, the first element in source that passes the test specified by predicate. Usage Note In Visual Basic and C#, you can call this method as an instance method on any object of ...
default (TSource) if source is empty; otherwise, the first element in source. Usage Note In Visual Basic and C#, you can call this method as an instance method on any object of typeIEnumerable<TSource>. When you use instance method syntax to call this method, omit the first parameter. ...
Bug #13794TEXT cannot use empty string as default value Submitted:6 Oct 2005 7:28Modified:8 Oct 2005 9:40 Reporter:Qi LiuEmail Updates: Status:Not a BugImpact on me: None Category:MySQL ServerSeverity:S4 (Feature request) Version:5.0.13-rc-nt, 5.0.14-rcOS:Windows (Windows, Linux) ...
STRICT_TRANS_TABLES enforces this constraint, then it should be supported by mysqldump dumping the empty default value. The JDBC driver can do nothing to work around this issue, other than having the user add a sql_mode that isn't STRICT_TRANS_TABLES which breaks JDBC compatibility as well ...
If any component of an expression default value depends on the SQL mode, different results may occur for different uses of the table unless the SQL mode is the same during all uses. ForCREATE TABLE ... LIKEandCREATE TABLE ... SELECT, the destination table preserves expression default values...
[System.ComponentModel.TypeConverter(typeof(System.Configuration.WhiteSpaceTrimStringConverter))] [System.Configuration.ConfigurationProperty("defaultProvider", DefaultValue="AspNetSqlRoleProvider")] [System.Configuration.StringValidator(MinLength=1)] public string DefaultProvider { get; set; } Property Value St...
一、SQL DEFAULT 约束概述DEFAULT 约束在 SQL 中是一种非常有用的机制,它允许你在创建表时为列指定一个默认值。...二、CREATE TABLE 时使用 SQL DEFAULT 约束的示例假设我们要创建一个名为 “Persons” 的表,其中包含 “PersonID”(人员 ID,整数类型,为主键)、“FirstName...以下是创建 “Persons” 表并设...
Called to get the default SQL string to execute. คัดลอก virtual CString GetDefaultSQL( ); Return Value ACStringthat contains the default SQL statement. Remarks The framework calls this member function to get the default SQL statement on which the recordset is based. This might...